This Simple Method Helps Gujarat Farmers Store Excess Rain Underground for Summer Months

In parts of Gujarat, the same rain that floods a farmer’s field during the monsoon may be desperately needed just a few months later. Waterlogging can damage crops, while the long dry season that follows leaves farmers struggling for irrigation.

Biplab Ketan Paul began wondering if farmers could somehow save that excess rain instead of losing it. The answer became Bhungroo, a system developed in Gujarat that sends surplus monsoon water underground, where it can be stored and pumped back up during the dry season.

The idea tackles two problems at once: too much water during heavy rains and too little when crops need irrigation.

An idea born from Gujarat’s water crisis

Biplab Ketan Paul had spent years working with communities in Gujarat when the 2001 earthquake brought him closer to the region’s water problems. He saw farmers struggle with an unusual cycle: months of water scarcity followed by monsoon rains intense enough to leave their fields waterlogged.

Developed in response to Gujarat’s water crisis, Bhungroo turns excess rainwater from a problem into a seasonal water resource. Photograph: (TBI team)

That contradiction led to a practical question: could the excess rain flooding farms be stored underground and brought back when farmers actually needed it?

Working with engineers and local women farmers, whose knowledge of their soil, fields and rainfall shaped the process, Paul began developing what would eventually become Bhungroo. The first version of the rainwater filtration and storage system was ready in 2004, after years of experimentation and trial and error. 

The name itself refers to a hollow pipe in Gujarati, which is essentially at the heart of the idea.

So, how does Bhungroo work?

Bhungroo uses a fairly simple idea: move excess rainwater away from the surface and store it underground until farmers need it. 

A Bhungroo unit begins with a small cemented collection pit. During heavy rain, excess water from the farm flows into this pit. It is filtered and then directed through a pipe drilled deep into the ground, sometimes reaching around 100 metres.

Each Bhungroo system is designed around the farm’s soil, rainfall and underground aquifer conditions, making local knowledge central to its implementation.
Photograph: (Buckminster Fuller Institute)

Instead of allowing the rainwater to sit on the surface and damage crops, Bhungroo pushes it into suitable underground aquifer layers, where it can remain stored.

When the dry season arrives, farmers can pump the stored water back up for irrigation.

In simple terms, the ground beneath the farm becomes a seasonal water bank: farmers deposit excess rain during the monsoon and draw on it when their fields need water months later.

The system also helps reduce waterlogging and evaporation losses. In saline regions, the stored rainwater can help reduce the salinity of groundwater, making agricultural land more productive. Depending on the soil, rainfall and aquifer conditions, a Bhungroo unit can store large quantities of monsoon water underground for later use. 

Why every Bhungroo has to be designed differently 

A key part of Bhungroo is that there is no standard design that can simply be installed everywhere.

Soils, slopes, aquifers and rainfall patterns differ from one farm to another. Each system therefore has to be adapted to the land and underground water conditions of the place where it will be used.

That is also where farmers’ own knowledge becomes essential.

By storing rain underground instead of letting it run off or evaporate, Bhungroo helps farmers bridge the gap between wet and dry seasons. Photograph: (TBI team)

Women farmers are involved in identifying suitable locations and helping manage the system based on their understanding of the land. Under the model, five women can form a Bhungroo group. The system may be installed on one member’s land, while the stored water is shared among the group.

That means the technology can influence who has access to irrigation, crops and agricultural income too.

Women farmers are at the heart of the model 

Naireeta Services, founded by Trupti Jain, has worked to place women at the centre of Bhungroo’s implementation. For women farmers with limited access to irrigation and agricultural income, having water available beyond the monsoon can change how much they are able to grow and earn from their land. 

With water available through dry months, some women have been able to harvest two or three times a year. The resulting income and food security can reduce the need to migrate for work and help families stay rooted in their villages.

The technology has travelled beyond Gujarat too. It has been implemented across several Indian states and in countries including Bangladesh, Ghana and Vietnam. In 2007, Bhungroo received recognition through the World Bank India Development Marketplace, and it later received a UN Momentum for Change award for its work with women farmers.

As rainfall becomes increasingly unpredictable, Bhungroo offers one way of addressing a problem many farmers face: water arriving at the wrong time.

Women farmers play a key role in managing Bhungroo groups, sharing stored water and using it to grow crops beyond the monsoon. Photograph: (Rajat Ubhaykar)

More than two decades after its first version was developed, the principle remains straightforward: save excess monsoon water when there is too much of it, so farmers can use it when there is too little.

What began as a response to Gujarat’s flooded and water-scarce farms has since travelled to other parts of India and countries abroad. Yet every Bhungroo still begins with the same questions: how does the rain fall here, what lies beneath this particular patch of land, and what do the farmers who work it know about it?

This story is part of “India Invented This?” — The Better India’s weekly trivia series that uncovers the Indian minds, ideas and innovations behind inventions that have shaped the way we live. From ingenious solutions created by scientists and engineers to technologies developed in response to some of India’s biggest challenges, each story goes beyond the invention to explore the problem it solved, the impact it created and why it still matters today.